Exploring Toronto’s Hidden Waterfronts

“Waterfront” is a relative term. Torontonians tend to think of the waterfront as the place where they can see water, as the term implies. But the city also keeps a few extra waterfronts in the back, where there’s no water in sight. Just because you can’t see it, that doesn’t mean it’s not there.

The oldest waterfront, by far, is the steep hill that runs east-west between Davenport and St. Clair, which marks the former banks of the large inland sea left behind from the last Ice Age. Today, it’s mainly an excuse for cyclists to avoid going north of the Annex.

Heading south on the old lakebed toward Lake Ontario, the next shoreline lies just south of Front Street—hence the name—about half a kilometre from Toronto’s present-day waterfront. That was the edge of the lake when the city was originally founded as the Town of York in 1850. Between then and now, all of the intervening land was unceremoniously dumped there to make space for the expanding city. But as Toronto grew out into the lake, the water never gave ground.

Gazing out toward the Gardiner Expressway from Front Street, this former waterfront doesn’t look that convincing. There are only roads and buildings in sight—no water. But the people who erected those buildings know better, because throwing dirt in a lake doesn’t actually make the water table get any lower. If you took a backhoe to the parking lot across from the Air Canada Centre, for example, the hole you dug would quickly become a pond. When developers excavate foundations for new buildings in that part of the city, they might as well be building directly in the lake.

In order to build south of Front Street, the first step is to dig deep, to bedrock, which can be as much as 30 metres down. “When they filled this anywhere from 150 to 60 years ago, they weren’t terribly concerned about the material that they used,” says David Kusturin, the VP of program management at Waterfront Toronto. They would use the ashy remains of incinerated garbage, silt dredged straight out of the lake, and soil pulled from other construction sites. Altogether, it isn’t very structurally sound.

The process of filling in the lake was often a slapdash affair. During the latter half of the 19th century, Toronto’s harbour was growing quickly as an important commercial port. But as bigger boats started to arrive, they found that the original waterfront was too shallow from them to dock, so wharves were built that jutted out into the deeper water, allowing them to unload more easily. (Prior to that, they moored in the harbour and relied on smaller boats to bring their goods to shore.) With each new wharf that was built, the old ones were buried in a hurry, and warehouses were assembled on top to store all the goods that were coming into the city.

While boats were pulling the waterfront out to meet them in the lake, trains were pushing from behind. Half a dozen different railway companies were vying for space in Toronto during the late 19th and early 20th centuries, so they started building elevated tracks over areas of the waterfront where they wanted to expand. They would simply open the side door of the railway car and push out the dirt.

“You find strange and unusual things,” Kusturin says of the buried goods in the in-fill land. “At one excavation over by Fort York, they actually found whale bones, which is very unusual because there are no whales in Lake Ontario, obviously.” Kusturin guesses that the bones were from a museum or a travelling show, and they ended up getting dumped into the lake along with other trash and treasures, including thousands of glass bottles. (For a nice selection, check out Weird Things on Bathurst.)

Apart from misplaced cetaceans, excavations south of the old waterfront mainly reveal the old wharves and abandoned boats that no one bothered to move before dumping the in-fill. They aren’t considered archeologically significant, except for one sea-faring oddity that has yet to be discovered. “It was a strange cylindrical boat that was built by someone in the Toronto area,” says Kusturin. That someone was Frederick Augustus Knapp, who, in a display of tech-hype worthy of the digital news cycle, promised a revolutionary watercraft that he claimed would achieve a speed of 200 miles per hour. His design involved a wheel-mounted interior platform that continuously rolled back to centre while the exterior hull rotated around it. Needless to say, it didn’t work particularly well. (For the definitive history of “Knapp’s Folly,” as it was called, read our Historicist account here.) The petrified remains of the roller boat are thought to be somewhere below the Union Station railway viaduct, and will likely remain there.

In order to properly dig through the in-fill, builders have to first hold back the water that would otherwise come seeping in from the lake. The first step is to install a bathtub, or what’s technically called a secant wall. This is done by drilling holes in the ground all the way down to the bedrock, one metre in diameter and close enough to touch, and then filling them in with concrete. This secant wall serves no structural purpose, but it does a decent job of keeping the water out once they start excavating, and also doubles as a retaining wall.

In fact, even with this bathtub wall, the water would still come in from the bottom, because the bedrock in southern Ontario is shale, which is porous enough for water to flow through. So builders have to put a pump in the bottom, which stays there even after the building is finished, because the water never stops coming. They can’t pump the water back into the lake, as you might expect, because it’s considered to be contaminated from seeping past all the random junk and miscellaneous metals in the in-fill land, so they send it into the city’s waste-water system to be treated.

Like the bedrock, the concrete secant walls aren’t perfectly impermeable, so the next step is to apply a special material to the inside surface, which keeps any water that seeps through draining downward. When it gets to the bottom of the building, it enters a sump pit and is pumped away with the rest of the water that comes up from the bedrock. After that, an actual waterproof sheet is added to the drainage layer, and the bathtub is complete.

Building a giant bathtub to hold your waterfront development is a lot more expensive than the standard approach. In a normal building, the underground parking lot will cost $30,000 to $40,000 per stall. In Toronto’s waterfront, it costs $100,000. Developers can clearly cope with the mark-up, because people love to live on the water—just not in it.